The invention relates to the use of spilanthol, notably in the form of an Acemella oleracea extract, for its botulinum toxin-like action, i.e. for its ability to inhibit contractions in subcutaneous muscles, notably those of the face. It also relates to the use of the purified molecule or of the extract in an antiwrinkle cosmetic composition.
Botox® or botulinum toxin is a substance extracted from the bacterium called Clostridium botulinum. This toxin, injected into the face muscles, paralyses them, attenuating face wrinkles. It has notably been observed that Botox® is particularly effective in attenuating frown wrinkles, forehead wrinkles, crow's feet and nose crease wrinkles. The main disadvantage of Botox®however, lies in its toxicity, as its use under certain conditions can lead to death.
In other words, the problem is to develop a product that provides botulinum toxin-like properties, but without any toxicity.
In the context of his research, the Applicant observed that spilanthol, notably in the form of an Acmella oleracea extract, was able to effectively inhibit contractile activity in subcutaneous face muscles.
Acmella oleracea is a plant of the genus Acmella belonging to the Compositae-Heliantheae family identified under the numbers
This plant is also known under the following names: Spilanthus oleracea, Pyrethrum spilanthus, and Spilanthes acmella variety oleracea. 
Acmella oleracea is a small annual plant from South America measuring 40 to 60 cm in height. This fragile plant flowers year-round, producing many yellow flowers. The plant is easy to multiply with seeds and cuttings.
Acmella oleracea is notably used in cosmetic compositions as the source of a molecule called spilanthol.
Document JP 9175947 thus describes a composition for hair growth containing a Spilanthes oleracea extract as an active ingredient in fat, notably oil.
Document JP 6072858 describes a spilanthol-based composition for use as a bubble bath for its refreshing effect on the skin.
Document JP 60215610 describes a bath preparation with sedative and firming properties.
Document U.S. Pat. No. 6,387,398 describes the cosmetic use of a Spilanthes acmella extract, notably as a deodorant agent, for the feeling of freshness provided by Spilanthol. 
Document EP-A-1,352,640 concerns the use of Acmella oleracea (Gin-New-Kou) solely for its inhibiting effect on the formation of melanin with, as an application, anti-ageing indications.
The publication by Chakraborty, “local anaesthetic effect of Spilanthes acmella in experimental animal models” (XP009035381), discloses the local anaesthetic effect of Spilanthes acmella. 
The publication by Herdy, “effect of spilanthol jambu spilanthes oleracea extract on the action potential by recording of an atrial fiber” (XP002293685), stresses the ability of Spilanthol to generate arrhythmia when injected into isolated rabbit hearts.
The document by Stashenko, “volatile secondary metabolites from Spilanthes americana obtained by simultaneous distillation-solvent extraction and supercritical fluid extraction” (XP002293687), describes an extraction procedure for Spilanthes americana metabolites. In the introduction, it is indicated that this plant has analgesic and paralysing effects, notably when applied to the tongue.
To the Applicant's knowledge, no document on the state of the art describes the ability of spilanthol and moreover of Acmella oleracea to inhibit the contraction of subcutaneous muscles, notably those of the face.